References of "Archives des Sciences Physiques et Naturelles"
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See detailSur la capacité de saturation des combinaisons colloïdes
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in Archives des Sciences Physiques et Naturelles (1911), XXX

Spring, W. Archives des Sciences Physiques et Naturelles (1911), 30, 561-71; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). cf. C. A., 4, 138, 969 ... [more ▼]

Spring, W. Archives des Sciences Physiques et Naturelles (1911), 30, 561-71; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). cf. C. A., 4, 138, 969, 1911. This is a report of some suggestive expts. on the mutual adsorption relations of saponin, lampblack and filter paper. When varying amts. of saponin are added to a standard suspension of lampblack in water the solns. of high and of low conc. settle faster than do the intermediate ones. There is an optimum stability at a conc. of saponin between 2.0 and 3.5%. In an elec. field saponin moves toward the anode, lampblack toward the cathode. When saponin is added to a lampblack suspension and an elec. current is passed the lampblack moves toward the anode-a reversal of the direction which it exhibits when alone. When a suspension of lampblack is poured through a filter the paper retains a part of the lampblack and this retained portion cannot be removed by washing with water, even when the filter is reversed. But if a soln. of saponin be poured through the blacked filter a portion of the retained lampblack is given up and passes through with the soln. A crayon made by molding a mixture of wet clay with lampblack or finely ground graphite marks paper easily and leaves a mark which is erased with difficulty. If, however, a soln. of saponin be used to moisten the clay-lampblack mixture the crayon is harder, marks paper with difficulty and the mark is easily erased. Similar results are obtained when the paper, instead of the crayon, is impregnated with saponin. When filter paper pulp is mixed with a lampblack suspension and collected on a cloth filter, the pulp retains some of the lampblack and the amt. so retained is sensibly independent of the conc. of lampblack in the original suspension. The author makes certain applications to the action of soapy substances in the cleansing of fabrics and concludes that there exists a limiting "saturation capacity in the combinations between colloids" which is analogous to the saturation of one atom by chem. combination with another. [This conclusion is quite out of accord with the existing knowledge of the form of the absorption isotherm and is not supported by the evidence presented. Reprinted with the permission of the American Chemical Society. Copyright © 2010. American Chemical Society (ACS). All Rights Reserved. [less ▲]

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See detailSur une modification lente de la constitution des solutions de certains sels
Spring, Walthère ULg

in Archives des Sciences Physiques et Naturelles (1910), 29

Spring, Archives des Sciences Physiques et Naturelles (1910), 29, 145-56; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). Solns. of a number of ... [more ▼]

Spring, Archives des Sciences Physiques et Naturelles (1910), 29, 145-56; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). Solns. of a number of salts (KNO3, KBr, Na2SO4, K2Cr2O7, ZnSO4, CuCl2, CuSO4, MnCl2, AlCl3, etc.) prepared in 1905 and kept at ordinary temp. from the action of direct sunlight were examined at intervals during the following four years and were found to become more and more transparent. The degree of transparency was judged by the degree of luminosity in the soln. of a beam of light projected through it by an electric lantern (50 volts and 12 amp.). To ascertain if there had been any molecular change in the solns., during the four years the conductivities of the original and the four year old solns. were determined and compared. The cond. of the original solns. was determined from portions of the 4-year-old solns. which had been evaporated to dryness and redissolved to the original vol. In the majority of cases the 4-year-old solns. showed markedly smaller conds. This may be explained by a hydrolysis of the salt which occurs when the soln. is first made. The "hydrate" [hydroxide?] thus formed is in a colloidal condition and does not affect the electrical resistance; this colloidal soln. by reflection renders more luminous a beam of light passed through the soln. The free acid initially present is the cause of the high conductivity of the solution. In the old solns. the colloidal hydrate and the free acid have greatly decreased, and the conductivity is therefore smaller than before. The state of equilibrium of such a hydrolysis, when once displaced by change of temp., etc., is restored very slowly. The soln. becomes more optically transparent owing to the gradual disappearance of the colloidal hydrate. The K2Cr2O7 soln. alone was anomalous and showed a decrease in resistance of almost one-half on standing four years. This soln. had become yellow, but on evaporating the soln. and redissolving to the same vol. the color was reddish yellow as in the original soln. Reprinted with the permission of the American Chemical Society. Copyright © 2010. American Chemical Society (ACS). All Rights Reserved. [less ▲]

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See detailSur la couleur du glycol éthylénique et de la glycérine
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in Archives des Sciences Physiques et Naturelles (1908), 25

Spring, W. Archives des Sciences Physiques et Naturelles (1908), 25, 5-14; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). Glycol and Glycerol, if ... [more ▼]

Spring, W. Archives des Sciences Physiques et Naturelles (1908), 25, 5-14; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). Glycol and Glycerol, if diluted slightly with water, lost their brown tint on filtration through animal charcoal and showed a blue color when observed through a long tube. The color was deeper than that of water or ethyl alcohol, indicating that the depth of color bears a relation to the number of hydroxyl groups present. Reprinted with the permission of the American Chemical Society. Copyright © 2010. American Chemical Society (ACS). All Rights Reserved. [less ▲]

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See detailSur les modifications subies par quelques phosphates acides à la suite d'une compression ou d'une déformation mécanique
Spring, Walthère ULg

in Archives des Sciences Physiques et Naturelles (1907), 23

Spring, W. Archives des Sciences Physiques et Naturelles (1907), 23, 229-45; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). The author subjected ... [more ▼]

Spring, W. Archives des Sciences Physiques et Naturelles (1907), 23, 229-45; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). The author subjected several acid phosphates to high pressures in a specially constructed cylinder with the following results: Ca(H2PO4)2H2O loses first its water of crystallization and finally a portion of the phosphoric acid, these two constituents being forced out of the compression cylinder. In general those constituents which were capable of liquefying under the pressure were found to be eliminated most readily. The acid phosphates of calcium, sodium and probably lithium form molecular compounds with their respective sulphates, that of calcium being insoluble in water and probably constituting one of the causes of reversion. Reprinted with the permission of the American Chemical Society. Copyright © 2010. American Chemical Society (ACS). All Rights Reserved. [less ▲]

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See detailSur les matières colorantes à base de fer, des terrains de sédiment et sur l'origine probable des roches rouges
Spring, Walthère ULg

in Archives des Sciences Physiques et Naturelles (1898), VI(4),

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See detailSur le spectre d'absorption de quelques corps organiques incolores et ses relations avec la structure moléculaire
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in Archives des Sciences Physiques et Naturelles (1897), 3

Spring, W. Arch. SC. phys. Genève (1897), 3(4), 437-63; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). The spectra water, several alcohols, ester ... [more ▼]

Spring, W. Arch. SC. phys. Genève (1897), 3(4), 437-63; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). The spectra water, several alcohols, ester, acids, halogen compounds, nitro compounds, the acetone, sugar canes, Benzaldehyde and several aliphatic and aromatic hydrocarbons were examined. The lengths of the tubes stood in the relationship of the molecular weights and amounted for example for methanol 4 m, for amyl acetate 15 m. If one fills the one of two behind tubes each other present with water, the other one with alcohol, then one obtains the absorption spectrum of both liquids beside each other, and the same also takes place, if a layer aqueous alcohol is observed by appropriate thickness. The temperature does not exert influence, reference of the color of the liquids the earlier by the new observations (Bulletin of the Royal Academy of Belgium, [3.] 31. 246; C. 96. II. 75) confirms the observations. With the cyclic hydrocarbons blue fluorescence could be observed by lateral lighting of long tubes. This seems to be peculiar with the benzene core; only in the turpentine oil fluorescence is missing, perhaps the long side chains cover the influence of the benzene core. By the apparent colorless liquids those seem of symmetrical building to give for example carbon tetrachloride and carbon disulfide no absorption bands while an asymmetrical distribution of the substituents causes band spectrum. The number and situation of bands additives a characteristic is multiple, for example the esters possess the absorption bands alcohol and the acid. Only when very close combination of two groups, the same affect of each other in such a manner that the bands of the two components of the molecule shift their situation or to fall a resulting band together. This present is for example with the homologous of the case of benzene, with the benzene band approaches the methyl band are the more groups of methyls in the molecule. With the halogen derivatives occur a weak shift of the bands toward the breakable part of the spectrum, if chlorine by bromine, and if bromine is replaced by iodine. When general result of the numerous, discussed in detail relations between structure and absorption spectrum of the colorless compounds regard in conformity with the opinions of Kekule an organic compound is to be regarded as a system, in which the individual groups lost their individuality not yet completely. Reprinted with the permission of the American Chemical Society. Copyright © 2010. American Chemical Society (ACS). All Rights Reserved. [less ▲]

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See detailSur le rôle des courants de convection calorifique dans le phénomène de l'illumination des eaux limpides
Spring, Walthère ULg

in Archives des Sciences Physiques et Naturelles (1896), I(4),

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